Google home nest thermostat and 7 wires going to 6 wire nest connector,

[philgreat61]

I have the NEST thermostat with 6 wire connecter on it Y C W on left and G R and OB on the right! the Heating guy that was here to install did not label or take photo of old thermostat of the 7 wires coming through the wall and just left - HE connected yellow to Y and Black to C and White to W on right side thermostat he has Green to G and Red to R and ORANGE and BLUE connected together to OB terminal - I Ran the wireless app test - and google home app says C is not getting any Power! any clues anyone- Thank you

[Markjosephp]

Hello philgreat61,

Thanks for reaching out!. It sounds like you're having some trouble with your Nest Thermostat installation, and there appears to be an issue with the C-wire connection.

Firstly, make sure that the C wire is securely connected to the C terminal on the thermostat. Double-check the connection at both ends—the thermostat and the HVAC system. If it's still showing no power, here are a few things you can try:

• Ensure that your HVAC system is providing power to the C wire. You may want to turn off the power, check the connections, and turn it back on.
• If you have a multimeter, you can measure the voltage between the R and C terminals to see if the C wire is getting power. It should typically read around 24 volts.
• Confirm that your HVAC system is compatible with the Nest Thermostat. Some systems may require additional components, like an external transformer, if they don't provide power to the C wire.
• If the HVAC system has seven wires, ensure that there isn't an additional hidden wire that wasn't connected. It's possible that the missing wire is causing the issue.

Let us know how it goes.

Best regards,
Mark